Seaweed‐derived polymer‐based blue‐emitting C‐dots: synthesis, characterization and evaluation for iron sensing

Abstract In recent times green and economical processes as well as sources have been in demand for the synthesis of carbon dots (C‐dots). This study demonstrates the smart utilization of seaweed‐derived polysaccharide as a green precursor for the synthesis of blue‐emitting fluorescent C‐dots using a simple, eco‐friendly and green method in an aqueous medium. The C‐dots prepared in this study were characterized using various techniques. The results confirmed that the prepared C‐dots have a cluster size of 100 nm with particle sizes in the range 5–10 nm. Prepared C‐dots emit blue photoluminescence with a good quantum yield of ca 12%. Additionally, strong fluorescence quenching of C‐dots is observed in aqueous solution containing iron ions, and a selective decrease in fluorescence intensity makes it possible to determine iron in water samples in the range 0.025 to 30 ppm. Results of this work encourage us that abundantly available seaweed‐derived polysaccharides with no other commercial value could be used as green sources for the sustainable production of fluorescent, water‐soluble and biocompatible nanocarbon for selective iron sensing in aqueous solutions. © 2021 Society of Chemical Industry